Question 1

Explain why hydrostatic equilibrium results in the center of the Sun having the highest pressure and temperature.

Accepted Answer

Hydrostatic equilibrium means that,at an...

Question 2

Observations of sunspots led to the discovery of the Sun's:

Accepted Answer

A)   coronal holes.
B)   coronal mass ejections.
C)   differential rotation.
D)   all of the aboveE) None of the above
F) A) and B)

Question 3

Through hydrogen fusion,the Sun loses approximately 4 million tons of mass each second.If it burns hydrogen at this rate for 10 billion years,what percentage of its original mass will it lose in all? (Note: The mass of the Sun is 1.99 × 10³⁰ kg,and 1 ton = 1,000 kg.)

Accepted Answer

The total amount of mass lost is
4,000 ×...

Question 4

Explain why magnetic fields trap coronal gas over much of the solar surface but allow it to escape in coronal holes.

Accepted Answer

Most of the solar magnetic field consist...

Question 5

Approximately what is the temperature at the center of the Sun?

Accepted Answer

A)   1500 K
B)   15,000 K
C)   15 million K
D)   15 billion KE) C) and D)
F) All of the above

Question 6

Show that a star with the same mass,composition,radius,and luminosity as the Sun,but with a higher temperature (that is,a "too-hot" Sun),leads to a contradiction.

Accepted Answer

If the temperature is higher,more energy...

Question 7

In the figure below,label the regions of the Sun.

Accepted Answer

The inner region is the core,t...

Question 8

Density,temperature,and pressure ________ as you move inward in the interior of the Sun.

Accepted Answer

A)   increase
B)   decrease
C)   stay the same
D)   There is not enough information provided.E) B) and D)
F) B) and C)

Question 9

When two atomic nuclei come together to form a new species of atom,it is called:

Accepted Answer

A)   nuclear fission.
B)   nuclear fusion.
C)   nuclear splitting.
D)   nuclear recombination.E) A) and C)
F) All of the above

Question 10

Why is hydrogen burning the main energy source for main-sequence stars?

Accepted Answer

A)   Hydrogen is the most common element in stars.
B)   Hydrogen nuclei have the smallest positive charge.
C)   Hydrogen burning is the most efficient of all fusion or fission reactions.
D)   All the above are valid reasons.E) None of the above
F) A) and C)

Question 11

Examine the figure below.Explain why it takes so long for gamma-ray energy to find its way to the outer layers of the Sun.

Accepted Answer

Gamma-ray radiation travels only short p...

Question 12

We can determine how the density changes with radius in the Sun using:

Accepted Answer

A)   radar observations.
B)   neutrino detections.
C)   high-energy (gamma ray)  observations.
D)   helioseismology.E) C) and D)
F) All of the above

Question 13

If a sunspot appears one-third as bright as the surrounding photosphere,and the average temperature of the photosphere is 5800 K,what is the temperature of the gas in this sunspot?

Accepted Answer

A)   4100 K
B)   4400 K
C)   5200 K
D)   5500 KE) B) and D)
F) B) and C)

Question 14

Illustrate the steps by which hydrogen is fused into helium in the Sun in the proton-proton chain.

Accepted Answer

In the first step,colliding protons crea...

Question 15

Which of the following are manifestations of solar magnetic activity?

Accepted Answer

A)   sunspots
B)   prominences
C)   flares
D)   all of the aboveE) A) and D)
F) All of the above

Question 16

Detection of solar neutrinos confirms that:

Accepted Answer

A)   the Sun's core is powered by proton-proton fusion.
B)   transport by radiation occurs throughout much of the solar interior.
C)   magnetic fields are responsible for surface activity on the Sun.
D)   convection churns the base of the solar atmosphere.E) A) and D)
F) All of the above

Question 17

When solar activity is very high,Earth's atmosphere will:

Accepted Answer

A)   expand.
B)   contract.
C)   remain approximately the same.
D)   repel charged particles.E) C) and D)
F) A) and B)

Question 18

Which of the following layers of the Sun makes up the majority of its interior?

Accepted Answer

A)   the core
B)   the radiative zone
C)   the convective zone
D)   the photosphereE) A) and D)
F) B) and D)

Question 19

The majority of the Sun's energy comes from:

Accepted Answer

A)   gravitational contraction.
B)   its rapid rotation.
C)   hydrogen fusion.
D)   helium burning.E) A) and C)
F) A) and D)

Question 20

The bulk of the Sun's energy generation is contained within a region of:

Accepted Answer

A)   0.2 solar radii.
B)   0.5 solar radii.
C)   0.75 solar radii.
D)   1.0 solar radii.E) A) and C)
F) None of the above

Exam 11: Our Star: the Sun

If a sunspot appears one-third as bright as the surrounding photosphere,and the average temperature of the photosphere is 5800 K,what is the temperature of the gas in this sunspot?

Correct AnswerverifiedShow Answer

The bulk of the Sun's energy generation is contained within a region of:

Correct AnswerverifiedShow Answer

Show that a star with the same mass,composition,radius,and luminosity as the Sun,but with a higher temperature (that is,a "too-hot" Sun),leads to a contradiction.

Correct AnswerverifiedIf the temperature is higher,more energy...View AnswerShow Answer

Which of the following layers of the Sun makes up the majority of its interior?

Correct AnswerverifiedShow Answer

When solar activity is very high,Earth's atmosphere will:

Correct AnswerverifiedShow Answer

Why is hydrogen burning the main energy source for main-sequence stars?

Correct AnswerverifiedShow Answer

Examine the figure below.Explain why it takes so long for gamma-ray energy to find its way to the outer layers of the Sun.

Correct AnswerverifiedGamma-ray radiation travels only short p...View AnswerShow Answer

Explain why magnetic fields trap coronal gas over much of the solar surface but allow it to escape in coronal holes.

Correct AnswerverifiedMost of the solar magnetic field consist...View AnswerShow Answer

Explain why hydrostatic equilibrium results in the center of the Sun having the highest pressure and temperature.

Correct AnswerverifiedHydrostatic equilibrium means that,at an...View AnswerShow Answer

The majority of the Sun's energy comes from:

Correct AnswerverifiedShow Answer

When two atomic nuclei come together to form a new species of atom,it is called:

Correct AnswerverifiedShow Answer

Detection of solar neutrinos confirms that:

Correct AnswerverifiedShow Answer

Approximately what is the temperature at the center of the Sun?

Correct AnswerverifiedShow Answer

Observations of sunspots led to the discovery of the Sun's:

Correct AnswerverifiedShow Answer

We can determine how the density changes with radius in the Sun using:

Correct AnswerverifiedShow Answer

Illustrate the steps by which hydrogen is fused into helium in the Sun in the proton-proton chain.

Correct AnswerverifiedIn the first step,colliding protons crea...View AnswerShow Answer

Density,temperature,and pressure ________ as you move inward in the interior of the Sun.

Correct AnswerverifiedShow Answer

In the figure below,label the regions of the Sun.

Correct AnswerverifiedThe inner region is the core,t...View AnswerShow Answer

Through hydrogen fusion,the Sun loses approximately 4 million tons of mass each second.If it burns hydrogen at this rate for 10 billion years,what percentage of its original mass will it lose in all? (Note: The mass of the Sun is 1.99 × 10³⁰ kg,and 1 ton = 1,000 kg.)

Correct AnswerverifiedThe total amount of mass lost is4,000 ×...View AnswerShow Answer

Which of the following are manifestations of solar magnetic activity?

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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Correct Answer
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If the temperature is higher,more energy...
View Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
verified
Gamma-ray radiation travels only short p...
View Answer

Correct Answer
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Most of the solar magnetic field consist...
View Answer

Correct Answer
verified
Hydrostatic equilibrium means that,at an...
View Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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In the first step,colliding protons crea...
View Answer

Correct Answer
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Correct Answer
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The inner region is the core,t...
View Answer

Correct Answer
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The total amount of mass lost is
4,000 ×...
View Answer

Correct Answer
verified